1. Field of the Invention
This invention generally relates to providing control signals to an aftermarket component installed in a vehicle. More specifically, the invention relates to a steering wheel control interface that can detect particular vehicle and aftermarket component configurations and properly transmit steering wheel control signals to the aftermarket component.
This invention also generally relates to providing two-way (bi-directional) translation of signals between factory vehicle modules and an aftermarket component installed in a vehicle.
2. Description of Related Art
Vehicle owners often seek to replace factory-installed audio and video components with aftermarket components. These aftermarket components often must be hard-wired to a vehicle's factory wiring. This may require that a user connect various power, audio, and video wires, and further that the aftermarket component communicate and operate, in part, through such wiring. Many modern vehicles include controls on their steering wheels for operating factory-installed components. These steering wheel controls (SWC) may, for example, increase the volume of a radio, increase the track of a CD being played, or change from one audio source to another. However, the particular configuration of a vehicle's steering wheel controls differs significantly among vehicle makes, models, and model years. Accordingly, it is very difficult for manufacturers of aftermarket components to provide compatibility between their components and the wide array of steering wheel control configurations.
U.S. Pat. Nos. 7,020,289 and 6,956,952 describe hard-wired interfaces for handling SWC signals. A commercial product similar to such interfaces is a SWI-JACK interface manufactured by the Pacific Accessory Corporation (PAC). The SWI-JACK interface has a wire harness on an input side and an output plug on an output side. To install the input side, an installer first selects a particular wire from among many included on the wire harness. The selection is made based upon a lengthy chart, which indicates suitable wires for particular vehicle makes and models. Once selected, the installer electrically connects the selected wire to a steering wheel audio control wire, which provides an output signal from the steering wheel audio controls. The SWI-JACK interface is geared to audio control wires provided within the steering column or underneath the vehicle's dashboard. To install the output side, the installer couples the output plug to a wired remote-control input on an aftermarket head-unit. Once the input and output sides have been installed, the installer completes installation by adjusting an input switch on the SWI-JACK. The adjustment is made according to the manufacturer of the aftermarket head unit.
There are several drawbacks to an interface such as the SWI-JACK. First, the interface is not designed to function upon installation. Rather, the installer must perform a lengthy programming process, with pressing and releasing the respective buttons on the steering wheel controls according to an installation sequence. The process is not only lengthy, but unforgiving. If the installer does not correctly perform the sequence, he must start the sequence over. Second, there can be several wires provided within a vehicle's steering column or dashboard. As a result, the installer may choose the wrong wire when attempting to electrically connect the interface to the steering wheel audio control wire. This could permanently damage components within the vehicle and compromise vehicle safety. A related drawback results from requiring the installer to choose a particular wire from the many wires of the wiring harness: if the installer selects the wrong wire from the harness, damage or malfunction to either the SWI-JACK or the vehicle can result. Furthermore, an inherent drawback of passive component interfaces, such as the SWI-JACK, is that they are compatible only with a limited number of manufacturers of aftermarket radios.
Another type of interface incorporates wireless transmission to relay SWC signals to the aftermarket component. Products manufactured with this design include the SWI-X interface by PAC and the REMOTE series interface by SoundGate. Generally speaking, these interfaces have a wire harness and an infrared (IR) receiver on an input side, and an IR transmitter on an output side. Installation of the input side proceeds in a manner similar to that described above in connection with the SWI-JACK. Installation of the output side involves mounting and aiming the IR transmitter such that it can communicate with an IR receiver integrated with the aftermarket component.
This design has several limitations, one of which is the lengthy programming process. The input and output sides having been installed, the installer must perform a wireless remote control “learning” process. For each steering wheel audio control button, the installer must use the remote control provided with the aftermarket component to emit an IR signal to the interface's IR receiver. The interface then “learns” the IR signal and stores its signal format for future reproduction, similar to a process used in learning television remote controls. The interface cannot reproduce an IR signal according to the steering wheel audio control inputs until this learning process has been performed.
The wireless interface design also fails to overcome the drawbacks of the SWI-JACK interface. The installer must connect the appropriate steering wheel audio control wire, risking permanent damage and malfunction to the vehicle and the interface. And if the installer incorrectly performs any part of the programming process, he must start over, leading to frustration.
Some methods of communication between a vehicle's electrical components are known. U.S. Pat. Nos. 7,275,027, 6,114,970, 6,823,457, 6,141,710, and 6,396,164 describe interconnections between a factory-configured vehicle bus (OEM bus) and a device bus for aftermarket products and accessories. These interconnections generally use a gateway controller. However, in these devices, the vehicle and device bus structures are predetermined. In this configuration, the gateway controller merely translates between a single set of OEM bus commands and a single set of device bus commands. Thus, these gateway controllers are tied to a specific vehicle bus and/or device bus architecture. Accordingly, they are inapplicable to universal aftermarket products.
In addition to interfacing steering wheel controls with aftermarket stereos, there is also a need in the art to interface other vehicle components to provide the same integrated vehicle experience as factory OEM stereos. For instance, modern-day vehicles include multiple displays to provide the driver and passengers with vehicle information, climate control (HVAC) settings, navigation prompts, backup camera images, Bluetooth call information, and audio and video track information (e.g., current song being played on an AM/FM radio station, or satellite radio station, MP3 song information). If the vehicle even partially relies on the factory stereo to operate these features, such features will conventionally be lost when the factory stereo is replaced with an aftermarket stereo.
Furthermore, many modern vehicles integrate the factory stereo, HVAC controls, and information displays into the vehicle dashboard, such that replacing the factory stereo with an aftermarket stereo often requires removal of the entire dashboard. For the vehicle manufacturers, this approach provides an integrated appearance and also deters the replacement of the factory stereo, encouraging vehicle purchasers to select a premium version of the factory stereo upon purchase. In such an instance, the HVAC controls and information displays may not be re-installable after installation of the aftermarket stereo, as the dashboard panel is not reused.
FIG. 7 shows a system diagram of a data bus 700 and the factory components communicating via the bus, in a conventional vehicle. Vehicle bus 700 is connected to at least one processor, such as vehicle information processor 710. Vehicle information processor 710 processes vehicle information transmitted along vehicle bus 700 to provide a user interface. Examples of such user interfaces include, but are not limited to, GM OnStar, Ford Sync, Chrysler BlueConnect, etc.
Vehicle bus 700 is also connected to various information displays, such as a heads-up display 720, an instrument cluster display 721, and a central information display 722. Heads-up display 720 projects an image onto the windshield, so that the driver is able to view vehicle information without shifting his or her eyes off the road. Instrument cluster display 721 is located within the instrument cluster and provides vehicle information. Central information display 722 is located in the central area of the dashboard and provides vehicle information.
Each display may, by default, display pre-established information types in accordance with any desired format. As one example, heads-up display 720 may customarily display vehicle speed, engine RPM, and/or navigation turn-by-turn prompts, instrument cluster display 721 may customarily display vehicle status, odometer, and/or miles-per-gallon (MPG) measurements, and central information display 722 may customarily display HVAC settings, stereo and song information, and/or navigation maps. In some instances, the vehicle may even permit the driver to customize the default information types provided in each display.
Each display may additionally be configured such that a specific condition triggers a momentary change in the type of information being displayed. As one example, a driver's modification of HVAC settings may cause heads-up display 720 and/or instrument cluster display 721 to momentarily display the modified HVAC settings. As another example, a transition to the next song in an MP3 playlist may cause heads up display 720, instrument cluster display 721, and/or central information display 722 to momentarily display the artist and title of the new current song. It will be appreciated that any condition trigger may be incorporated to produce a momentary change in displayed information in each display, in accordance with a desired operation of the vehicle.
Vehicle bus 700 is further connected to a factory stereo 730. Factory stereo 730 include a display (not shown) that provides pre-established information types and may also provide a momentary change in information type, in the same manner described above with respect to heads up display 720, instrument cluster display 721, and central information display 722.
Factory stereo 730 may communicate with control modules both via direct connections and via vehicle bus 700 to execute functions associated with factory stereo 730. Control modules include the vehicle information processor 710, a factory audio amplifier 740, a satellite radio module 741, a Bluetooth module 742, a navigation module 743, a speech processor module 744, and a central control module 745.
Vehicle information processor 710 provides signals, such as audio signals, to factory stereo 730 over a direct connection 762. Vehicle information processor 710 also communicates with factory stereo 730 via vehicle bus 700 to transmit and/or receive other signals, such as control or status signals.
Factory audio amplifier 740 receives audio signals from factory stereo 730 over a direct connection 764, and amplifies and plays the audio signals through the vehicle's speakers. Direct connection 764 may be an analog connection for transmission of line-level audio signals, or may alternatively be a digital connection such as a dedicated secondary bus for transmission of digitally-encoded audio signals for decoding by factory audio amplifier 740. Factory audio amplifier 740 also receives signals such as control signals (e.g., controlling volume, balance/fade, treble/bass), and sends signals such as status signals, over vehicle bus 700.
Satellite radio module 741 provides access to satellite radio stations for factory stereo 730. Satellite radio module 741 receives and decodes satellite signals corresponding to satellite radio stations from a satellite antenna. Satellite radio module 741 transmits the decoded audio to factory stereo 730 via direct connection 765. Satellite radio module 741 also communicates with factory radio 730 via vehicle bus 700, such as sending status signals (e.g., text information, channel numbers), and receiving control commands from factory stereo 730 in accordance with a desired operation (e.g., changing satellite radio stations).
Bluetooth module 742 provides a Bluetooth interface for factory stereo 730. Bluetooth module 742 receives wireless signals over Bluetooth protocol from a cellular telephone or any other Bluetooth device. Bluetooth module 742 provides audio signals to factory stereo 730 over direct connection 766. Bluetooth module 742 also communicates with factory radio 730 via vehicle bus 700, such as sending data (e.g., caller ID, text messages, status), and receiving control commands to control the Bluetooth device. With the Bluetooth module 742, the factory stereo 730 may provide hands-free telephone calls, streaming Bluetooth audio, display of text messages, Internet access, mobile hotspot, or any other feature available via a Bluetooth connection.
Navigation module 743 provides navigation abilities for factory stereo 730. Navigation module 743 receives location signals such as GPS signals, renders a continuously-updating mapping display, and provides this video map to factory stereo 730 over direct connection 767. Navigation module 743 may also store map and points-of-interest data and incorporate this information in the video map. Navigation module 743 may also provide turn-by-turn audio prompts, and provide this audio to factory stereo 730 over direct connection 767. Navigation module 754 also communicates with factory stereo 730 via vehicle bus 700, such as transmitting additional signals (e.g., supplemental navigation information, status), and receiving signals (e.g., control signals to adjust video map). Factory stereo 730 may also provide navigation information to other vehicle displays such as heads-up display 720, instrument cluster display 721, and central information display 722 via vehicle bus 700.
Speech module 744 provides speech processing abilities for announcements that are played through factory stereo 730. For instance, factory stereo 730 may use speech module 744 to announce navigation prompts, Bluetooth caller ID, song/title information, or any other information. Factory stereo 730 may also receive and process requests from other vehicle components (e.g., vehicle information processor 710) to play announcements as instructed by those vehicle components. In addition, speech module 744 may provide speech-recognition functions. That is, speech module 744 may also receive audio clips of a driver or passenger's speech, and decode the audio clips into voice commands corresponding to a vehicle action. Speech module 744 transmits and/or receives audio from factory stereo 730 via a direct connection 768. Speech module 744 also communicates with factory stereo 730 via vehicle bus 700, such as control and/or status signals. Speech module 744 may communicate with the other vehicle modules over vehicle bus 700 as appropriate, for execution of the desired voice command.
Central control module 745 provides user input for controlling vehicle functions including those on factory stereo 730. Examples of a central control module 745 include a centrally-positioned joystick, wheel, slide, touchpad, button assembly, or any other user input type. Central control module 745 transmits user inputs over vehicle bus 700 to modules such as factory stereo 730.
Vehicle bus 700 is also connected to a backup camera 750 and rear-seat entertainment 751, such as rear-seat video screens and/or headphone jacks. Backup camera 750 provides video signals over direct connection 763 to factory stereo 730 to display when the vehicle is operated in reverse gear. Rear-seat entertainment 751 receives audio and/or video signals from factory stereo 730 via direct connection 769 to provide rear seat occupants with additional audio and/or video entertainment source(s) that play independently from primary audio and/or video selections being played and controlled by the front-seat occupants. Backup camera 750 and rear-seat entertainment 751 additionally communicate with factory stereo 730 via factory bus 700, to transmit and/or receive status and control signals.
Vehicle bus 700 may also be connected to steering wheel controls 760. As already described, steering wheel controls 760 are buttons on the steering wheel of the vehicle that allow a driver to control various functions on factory stereo 730. On some vehicles, steering wheel controls 760 may not be connected to vehicle bus 700, but may instead be connected to factory stereo 730 via a direct connection 761.
Vehicle bus 700 is also connected to an HVAC control module 770 and HVAC controls 771. HVAC controls 771 allow operator adjustments of climate control settings, and such adjustments are transmitted to HVAC control module 770 via signals over vehicle bus 700. HVAC controls 771 may include knobs, buttons, or any other user control interface. HVAC control module 770 controls the heating and cooling systems of the vehicle in accordance with signals received from HVAC controls 771.
It will be appreciated that direct connections 761-769 are traditionally analog connections, but may alternatively be digital connections or secondary data busses, with the appropriate encoders and decoders to perform conversion between digital and analog. It will also be appreciated that while direct connections 761-769 may each constitute a single wire or multiple wires, or may even be a wireless connection. It will further be appreciated that while digital connections 761-769 are described as separate connections for each vehicle module, these connections may be shared connections, such that multiple modules utilize a common connection. It will still be appreciated that the vehicle modules may be alternatively configured to solely utilize vehicle bus 700 for communication, instead of additionally using the corresponding direct connections as described.
A problem arises when factory stereo 730 is replaced with an aftermarket stereo. Upon such a replacement, many of the factory components, as described above with reference to FIG. 7, may be rendered partially crippled or even entirely inoperable. For instance, factory audio amplifier 740, satellite radio module 741, Bluetooth module 742, navigation module 743, speech module 744, central control module 745, backup camera 750, rear seat entertainment 751, and steering wheel controls 760 may not be directly compatible with the aftermarket stereo.
Additionally, heads-up display 720, instrument cluster display 721, and central information display 722 may not continue to display stereo information, as they are not directly compatible with the aftermarket stereo. Furthermore, installation of the aftermarket stereo may require the removal of HVAC controls 771 when such controls are integrally attached to factory stereo 730, so HVAC control module 770 will no longer receive signals for adjusting the climate control.
This problem occurs because conventional aftermarket stereos lack the functionality to interface and communicate with vehicle bus 700, as required to operate the factory modules. The problem is aggravated in that aftermarket stereos are designed to be broadly compatible, while vehicle data busses vary among different vehicle manufacturers and or even within the same manufacturer among different models or model years. Aftermarket stereos are not equipped to be universally compatible with all vehicle bus types. As such, the functionality of factory-installed modules is customarily lost when a factory stereo is replaced with an aftermarket stereo.
As the above discussion makes clear, there is a need to provide a simple, universal solution for providing SWC inputs of all makes and models to aftermarket radios from a wide variety of manufacturers. In particular, an installer can benefit from a device which automatically detects at its input an SWC signal and which configures itself accordingly. Additionally, installers can further benefit from a device which automatically detects an aftermarket component and which further configures itself accordingly. In this manner, the device allows for a simple “plug-and-play” installation process, reducing the stress and risks of installation for both professional and self-installers.
There is also a need to provide a simple, universal solution that retains the functionality of factory-installed components and modules when a factory stereo is replaced with an aftermarket stereo.